1. Field of the Invention
The present invention relates to a method of increasing recording density of a hard disc drive, and more particularly, to a method of increasing recording density in terms of tracks per inch (TPI) by using software.
2. Description of the Related Art
Hard disc drives are apparatuses for recording information, and more particularly, recording information onto concentric tracks of at least one side of a hard disc. A disc is rotatably mounted on a spindle motor, and information is accessed by using a magnetic head mounted on an actuator arm which is rotated by a voice coil motor. The voice coil motor is excited by a current so as to rotate the actuator, and thus, the magnetic head is moved.
A magnetic head includes a recording head and a reading head. If a recording current is applied to the recording head, the recording head stores information by magnetizing a region of the surface of a disc adjacent to the recording head. The reading head reads information recorded on the surface of the disc by detecting the change of magnetic property from the surface of the disc.
It is generally known that a perpendicular magnetic recording mechanism has a higher recording density than that of a horizontal magnetic recording mechanism. Thus, recently, most hard disc drives employ the perpendicular magnetic recording mechanism for increasing recording density.
In the perpendicular magnetic recording mechanism, a magnetization direction is arranged in a perpendicular direction to a plane of a medium. The perpendicular magnetic recording mechanism employs a perpendicular magnetic recording medium and a pole head. The perpendicular magnetic recording medium includes a double magnetic layer film of a ferro-magnetic layer and a soft magnetic under-layer (SUL). In order to record an information bit on the perpendicular magnetic recording medium using the pole head, an appropriate alternating current is applied to the pole head.
Many efforts to increase the TPI have been performed in hard disc drive (HDD) related industries. In this regard, studies to reduce a width of a write pole have been conducted. Also, in order to reduce a width of an erase band, a side shield is employed or hardware, such as a wraparound shielded (WAS) head that entirely surrounds the write pole, is employed.